The ICARDA durum wheat program to combat climate change

by Filippo M. Bassi, PhD Principal Investigator Genetic Innovations, ICARDA

Providing stress tolerant varieties to partners to adapt farming systems in Africa and Asia

The international center for agricultural research in the dry areas (ICARDA; www.icarda.org) was funded in 1977 in Beirut, Lebanon under the umbrella of the CGIAR. ICARDA’s mandate was to support via scientific innovations the dryland farming systems with a primary focus in Africa and Asia. Due to the unique importance of durum wheat especially in North Africa, Ethiopia, and West Asia, a breeding program for this crop was immediately established since inception.

The history of ICARDA breeding

Until 2003, the durum breeder position at ICARDA was funded by

CIMMYT, with the specific task to select among and recombine the Mexican germplasm to better adapt to the dryland conditions. The initial breeding activities of ICARDA were then to test among F5 populations developed by CIMMYT. This effort resulted in the first release in 1984 in Algeria of “Waha,” a cultivar later released also in Syria as “Cham 1” and which still occupies large cultivated areas. Soon after, the first variety originated by the crossing and selection program of ICARDA in Syria was achieved in 1989 in Morocco under the name “Omrabi,” later released in more than 17 countries because of its drought tolerance. This unique variety was obtained by combining the CIMMYT elite line “Jori” and the Syrian landrace

“Haurani,” and the success of this type of exotic cross marked the future of the ICARDA breeding program. In 2003 CIMMYT encountered some financial difficulties that resulted in the need of ICARDA to fully cover all breeding activities. Since then, the two centers operate in partnership but conduct independent breeding efforts with different strategies and goals. The ICARDA program primarily focuses in developing varieties for the drier zones, capable of withstanding the major local pests and the common severe droughts and heat waves. To achieve this, it utilizes extensively its genetic richness conserved in the genebank, taking advantage of the rare landraces and wild relatives to integrate novel traits for adaptation. Furthermore, ICARDA relies heavily on its national partners to conduct jointly field testing across more than 30 locations and 20 countries each year, ensuring the specific adaptation of the germplasm combined with strong stability. Over its 45 years of service, the ICARDA program has resulted in the release of more than 150 varieties across 23 countries.

The program of Dr Miloudi Nachit

From 1982 until 2014 (30 years), the durum breeding program was led by Dr. Miloudi M Nachit. Dr. Nachit used the stations of Tel Hadya in Syria and Terbol in Lebanon to deploy a breeding method he defined as “doublegradient selection,” which used different planting dates and irrigation amounts to substantially

Developing Varieties For Drier Zones

create six different environments in the early generations of selection. Dr. Nachit also pioneered the use of molecular markers in breeding, and published a paper on RFLP (restriction fragment length polymorphism) in durum wheat already in 1996. In 2009, he was knighted by the King of Morocco for his contribution in protecting Moroccan farmers from the threat of the Hessian fly (together with other Moroccan scientists). In 2015, the release of his variety “Utuba” in Ethiopia has saved the national durum production from the devastating effect of stem rust. In Syria, the breeding effort had resulted in 2009 to a country shift from an importer to a net exporter of durum grains. Unfortunately, the civil situation in Syria has obliged the ICARDA breeding program to relocate to Morocco in 2012, where it operates since.

Continuing from the past to the future

In 2013, Dr. Filippo M. Bassi joined Dr. Nachit’s team as an associate breeder, and in July 2014 he took over the program. In this transition the greatest strengths of the ICARDA program were further boosted, such as the establishment of even stronger partnerships and the continued heavy reliance on diverse germplasm to adapt to ever more challenging climatic conditions. The molecular work was expanded, with the ICARDA program becoming in 2022 the first durum program to be entirely run using the combination of genomic selection and speed breeding. The integration of stability analysis across actual diverse locations has now replaced the approach of simulating environments, taking full advantage of the natural environmental diversity that occurs in Morocco. New and more complex challenges have now been taken onboard, such as the will to increase beyond 60 gr the 1000-kernel weight or the goal to generate germplasm resistant against root or crown rot ( Fusarium spp. ). Additional examples of this farreaching vision can be the bestowing of the OLAM Prize for Innovation in Food Security obtained by developing varieties capable of withstanding growing temperature of up to 40 °C from planting to harvest along the Senegal River, or the recent achievement of deep rooted varieties capable of producing over 2 tons per hectare despite only 200 mm of total rainfall.

New challenges

With the climatic conditions changing ever so rapidly, resulting in dramatic combinations of heat, drought and pests’ stresses, the work of breeders has become more important than ever. It has become key to generate new germplasm primed with the genetic plasticity to adapt to changing conditions, maximizing productivities in good years while ensuring stable productions in bad ones. Maintaining the farms productive in the next decades will depend heavily in achieve these goals.

The ICARDA program is uniquely positioned to do so for durum wheat, thanks to its abundant genetic diversity, its field-testing network located in zones already experiencing tremendous climatic changes, and the deployment of the latest breeding methodologies. Nevertheless, climate change is the greatest challenge to ever be faced by modern humanity. Defeating it requires a combined effort by all: scientists, extension agents, educators, farmers, food producers, politicians, consumers and many more. ICARDA is ready to pick up this challenge and to partner with all to make it a success: would you join us in this fight?

Filippo M. Bassi, PhD